Access ramp



Nov. 10, 1970 G. Z. PORTER ETAL ACCESS RAMP 4 Sheets-Sheet 1 Filed Aug. 1, 1968 RTER INVENTORS.

N o s B o C A J N o D R o G GEORGE Z. PO

AT TORNEYS 1970 a. z. PORTER ETAL 3,533,523

ACCESS RAMP Filed Aug 1 1968 4 Sheets-Sheet 2 INVENTORS. GORDON JAGOBSON GEORGE Z. PORTER BY(QILE$Q,

ATTORNEYS Nov.10,1970 G. 2. PORTER Em 3,538,528

' ACCESS RAMP Filed Aug. 1, 1968 4 Sheets-Sheet 3 FIG D 90 I v U] a U 84 8% H l w "W 86 ""1, in!! 5 v 5' FIG 8 FIG FIG .IOI

GORDON JACOBSON GEORGE Z. PORTER INVENTORS.

ATTORNEYS Nov. 10, 1970 s. z. PORTER E'I'AL 3, 2

I ACCESS RAMP I I Filed Aug. 1, 1968 4 Sheets-Sheet 4 I24 I22 I52 d INPUT gm 1 l I III: v I40 I44 I42 i- DOWN LIGHTS HEATER F|G 86 I20 I54 I32 I24 1 I OUT 5 UP IN EMERCE NC Y DOWN G I 2 STOP '2 STAIR on I50 I22 woven RAMP LICH'I'OSFF HEATER I I I52 I26 I48 FIG l3 GORDON JACOBSON GEORGE Z. PORTER INVENTORS.

AT TORN E Y5 3,538,528 Patented Nov. 10, 1970 3,538,528 ACCESS RAMP George Z. Porter, Bellevue, Wash, and Gorden Jacobson, 741 S. 295th Place, Federal Way, Wash. 98002; said Porter assignor to said Jacobson Filed Aug. 1, 1968, Ser. No. 749,417 Int. Cl. Btig 11/00 US. Cl. l471 Claims ABSTRACT OF THE DISCLOSURE This invention relates to access ramps leading from above-ground structures. More particularly this invention relates to above-ground airline terminal passenger boarding or cargo loading ramps.

So-called second story airplane passenger boarding ramps commonly in use at airline terminals have the ability to be extended, retracted, raised, lowered, and and angularly positioned such that their outboard ends can be docked with an airplane in proper alignment with the airplane passenger doorway. These ramps, however, are large, complicated and expensive. Furthermore, such ramps are typically supported at their outboard ends by telescopic hoists mounted on steerable drive wheels. The utility of these ramps is limited to applications where there ramp surface need not slope greater than about to accommodate an airplane doorway. Consequently, these ramps are often too expensive and not sufficiently versatile to be incorporated into many of the smaller airline terminals.

Accordingly, a primary object of the present invention is to provide an above-ground airline terminal passenger boarding or cargo loading ramp of less complex construction weight and expense and of greater versatility than has been heretofore commercially available. A further object is to provide such an access ramp having an articulated ramp floor that can be converted from a fiat ramp surface to a stairway, and vice versa, as desired. Another object is to provide such a ramp as a cantilevered assembly. A still further object is to provide such a ramp with an extenda'ble outboard landing to permit mechanic access in an overhaul-maintenance dock, wheel chair boarding, galley service, crew access, and so forth.

These and other objects and advantages will become apparent from the following description and the accompanying drawing, of which:

FIG. 1 is a view of the side elevation of a preferred embodiment of the articulated access ramp of this invention;

FIG. 2 is atop plan view of the FIG. 1 embodiment;

FIG. 3 is a cross section view taken along the line 3-3 of FIG. 2;

FIG. 4 is a side elevation of the FIG. 1 embodiment with protective cover plates removed;

FIG. 5 is a schematic illustration of the articulated ramp linkage with the access ramp floor positioned in a ramp mode;

FIG. 6 is a schematic illustration of the articulated ramp linkage with the access ramp floor positioned in a stair mode;

FIG. 7 is a side elevation of the outboard landing assembly platform of the FIG. 1 embodiment;

FIG. 8 is a bottom plan view of the FIG. 7 landing assembly platform;

FIG. 9 is a detail cross section view of a portion of the FIG. 7 landing assembly taken along the line 9-9 of FIG. 1;

FIG. 10 is a bottom plan detail view of the outboard end of the landing assembly platform;

FIG. 11 is a schematic of the electrical control circuit employed with the FIG. 1 embodiment;

FIG. 12 is an exemplary electrical control panel employed with the FIG. 1 embodiment;

FIG. 13 is a detail elevation view taken along the lines 1313 of FIG. 1; and

FIG. 14 is a detail side elevation view illustrating the ramp mode aptuating assembly.

In brief, the access ramp of the present invention comprises a ramp assembly having a floor adapted to assume either a ramp mode or a stair mode, an outboard landing assembly mounted to the outboard end of the ramp assembly, and an eleevator assembly for supportramp assembly, and an elevator assembly for supportably raising and lowering the outboard end of the ramp assembly. The ramp assembly is adapted to be hingeably connected to a supporting structure at its inboard end such that raising and lowering of its outboard end causes he ramp assembly to swing about the hinged connection. The floor of the ramp assembly comprises a plurality of tread members, tread mounting means mounting the tread members, and articulated means linking the tread members and the tread mounting means and adapted to position the tread members either in a ramp mode or a stair mode as the ramp assembly is raised and lowered. The outboard landing assembly comprises a landing member, and a landing mounting means mounting the landing member and positioning the landing member to interrelate to the tread members when the latter are in either a ramp mode or a stair mode.

Referring to the figures, the preferred embodiment of the access ramp therein depicted comprises a ramp as sembly 10, an outboard landing assembly 12, and an elevator assembly 14. As shown in FIGS. 2, 4, 5 and 6, the ramp assembly comprises a plurality of tread members 16, tread mounting means in the form of left and right hand tread mounting arms 18 (shown schematically in FIGS. 5 and 6) and left and right hand lever arms 22 and 24 (shown schematically in FIGS. 5 and 6). The outboard landing assembly comprises a landing member 26 and left and right hand landing member mounting brackets 28 that guidably mount the landing member 26 and are themselves pivotally mounted at their respective upper end sections at point 30 to the outboard ends of the left and right hand tread mounting arms 18. The elevator assembly 14 comprises left and right hand ramp support arms 32, the outboard ends of which are pivotally connected at points 34 to the respective lower end sections of the left and right hand landing member brackets 28, and a raising and lowering mechanism 36. The inboard ends of the tread member mounting arms 18 are pivotally connected at points 38 to angle brackets 40, the inboard ends of the ramp support arms 32 are pivotally connected at points 42 to channel brackets 44, and the raising and lowering mechanism 36 is fixedly mounted by left and right hand A-frame brackets 46. Brackets 40, 44 and 46 are mounted to an elevated supporting framework such as the vertical wall of an airline terminal designated by the line 48 in FIGS. 1, 2, and 4 so that the ramp floor properly interrelates to an inboard landing 50 constituting an exit from the elevated framework.

Referring now specifically to FIGS. 3, 4, 5 and 6, each tread member 16 comprises a rectangular fioor plate 52 with left and right hand pivot arms 54 centered at the sides thereof and extended upwardly. The left and right hand pivot arms of each tread member are journal mounted to the inner faces of the left and right hand tread member mounting arms 18 at points 56, and are equispaced from one another along the arms 18 such that the adjacent leading and trailing ends of the floor plates 52 will abut one another when the arms 18 are horizontally positioned. The upper ends of the left and right hand pivot arms 54 are pivotally interconnected to the tie rods 20 at points 58, with the tie rods pivotally connected to and between the pivot arms being at all times parallel with the line of intersection of the pivot points 56, as shown in FIGS. 5 and 6. The inbroad ends of the inboard-most left and right hand tie rods 20 are pivotally mounted to the inboard ends of the left and right hand tread member mounting arms 18 at points 60, and the outboard ends of such tie rods are pivotally connected to the inboard ends of the next adjacent tie rods in the tie rod linkage at points 62 and are also at that point pivotally connected to the upper ends of the respective lever arms 22. The left and right hand lever arms 22 are intermediately journal mounted to the respective mounting arms 18 at points 64, and are pivotally connected at their lower ends to the respective outboard ends of the lever arms 24 at points 66. The inboard ends of the left and right hand lever arms 24 are provided with cam followers 68 adapted to track in semicircular slots 70 to left and right hand vertically-oriented brackets 72.

The upper sections of lever arms 22, defined by the pivot points 62 and 64, and the links defined by points 58 and 56 of the tread member pivot arms are parallel to one another and oriented at right angles to the links defined by pivot points 6258 and pivot points 6456 when the tread mounting arms 18 are horizontally positioned as shown in FIG. 5. Thus a rectangular geometry is defined by pivot points 56, 58, 62 and 64. With the left and right hand lever arms 24 positioned as shown in FIG. 5 with their cam followers 68 located at the upper end of the left and right hand semicircular cam tracks 70, the cam followers 68 will be aligned with the inboard pivot points 38 to the tread mounting arms 18 and, consequently, when the ramp assembly 10 is lowered by swinging the tread mounting arms 18 downward about pivot points 38 the pivot points 56, 58, 62, 64 and 66 will maintain the same relationship to one another as shown in FIG. 5. Therefore, the floor plates 52 of the tread members 16 will remain in edge to edge abutment as shown in FIG. 5 thereby becoming an inclined ramp.

When the left and right hand lever arms 24 are pivoted from the position shown in FIG. 5 about their respective pivot points 66 to the lower ends of the respective semicircular cam tracks 70, a parallogram relationship will be created between pivot points 38, 64, 66 and the thusassumed positions of the cam followers 68, and the upper sections of levers 22 as defined by pivot points 66 and 68 on the tread member pivot arms. When the ramp assembly 10 is then pivoted downward by swinging the tread member mounting arms 18 about their pivot points 38, pivot points 66 will now rotate about the thus-assumed positions of cam followers 68 such that the lever arms 22 will be positionally translated without rotation and the links defined by pivots 62 and 64 will remain vertically oriented as shown in FIG. 6. Consequently, the rectangular configuration defined by pivots 56, 58, 62 and 64 existing prior to downward movement of the ramp will be converted to a parallelogram configuration as shown in FIG. 6 with the result that the adjacent edges of the tread members will be displaced and the ramp assembly will break into steps as shown in FIG. 6.

It is thus seen that the left and right hand lever arms 24 determine whether the ramp asembly assumes a stair mode or a ramp mode by its position. The positions of the lever arms 24 are controlled by a suitable electric powered linear actuator designed to swing the arms between limit switches in unison, such as the screw type actuator 25 depicted in FIG. 14.

Referring to FIGS. 4, 7, 8, 9 and 10, the landing member 26 is provided along its left and right hand sides with outwardly opening guide channels 80. The left and right hand landing member mounting brackets 28 are each provided with forward and rearward sets of guide rollers 82 journal mounted to the inner face of each such mounting bracket, each roller set consisting of an upper roller designed to track on the inner surface of the upper leg of the respective guide channel and a lower roller designed to track on the inner surface-of the lower leg of the respective guide channel 80. Roller sets 82 are so mounted that the inboard end section of the landing member 26 extends beneath the tread members 16 and their mounting arms 18. The ramp assembly support arms 32 are pivotally connected outwardly of the landing member mounting bracket 28 such that the inwardly mounted landing member 26 and the arms 32 will not interfere with one another. The arms 32 are pivotally mounted as hereinbefore described such that they are parallel with the tread member mounting arms 18 so that the landing member 26, as guided by the roller sets of mounting brackets 28, will remain horizontally positioned regardless of the degree of inclination of the ramp assembly 10.

The landing member mounting brackets 28 are crossconnected beneath the landing member by an inverted channel cross beam 84, to the underside of which is mounted an electrically powered variable speed gear motor 86 for extending and retracting the landing member. The gear motor is provided with a double output linked with left and right hand drive chains 88 by drive sprockets 90, the ends of the drive chains being attached to the underside of the landing member at its inboard and outboard end sections. Upon actuation of the motor 86, the gear motor will drive the landing member for either extension or retraction as desired. A linear motion outboard position sensor 92 is mounted on the outboard end of the landing member 26 for detecting the approach of the outboard end of the landing member to an object, such as the doorway of a plane. The sensor 92 is electrically connected to the motor 86 to reduce the gear motor speed as the landing member outboard end approaches the desired position. The sensor 92 is preferably the type having a null indicating position which, when reached, will cause the motor 86 to halt the landing member and which, when exceeded, will cause the motor 86 to retract the landing member 26 until the null position is reestablished. The gear motor 86 is preferably provided with dynamic braking to preclude overrunning. This feature of the invention is particularly desirable when the ramp assembly is employed for loading and unloading an airplane inasmuch as movement of passengers or cargo onto or off an airplane will often cause slight shifting movement of the planes fuselage necessitating minor readjustment of the outboard end position of the landing member 26.

In the embodiment of the access ramp depicted in the drawings, the inboard end mounting of the ramp assembly is not of the type permitting lateral swinging and therefore an outboard docking assembly 94 is provided in the outboard end of the landing member 26 to insure firm engagement of the access ramp with, for example, an airplane fuselage even when the fuselage is not perpendicularly aligned with the access ramp. This docking assembly comprises a horizontal segment swing plate 96 pivotally mounted at its apex 98 to one edge of the landing member 26 and provided with a track 100 along its arcuate edge which tracks in rollers 102 mounted in the landing member 26 and resiliently urged outward by a spring and lever assembly 104. The outboard edge of the segment plate 96 is provided with a bumper or snubber 106 to provide resilient contact with an airplane fuselage.

The raising and lowering assembly 36 comprises left and right hand ball screw type linear actuators 110 pivotally mounted to the respective A-frame supports 46 and supporting arms 32 and driven by a variable speed electricmotor 112 which is mounted on a cross beam 114 that connects the outboard ends of the A-frame supports 46.

Referring now to FIGS. 11 and 12, the electrical control system for operation of motors 86, 112, and 120, is preferably designed to operate from a 110 volt AC. input and comprises a power on-off switch 122 which may be a key operated relay switch, and an emergency stop button switch 124 interconnected with the power switch 122 such that its activation will energize the coil on switch 122 to return the latter switch to its off position. The stairramp mode of the ramp assembly, as effected by actuator motor 120, is controlled by the position switch 126, with suitably placed limit switches 128 and 130 serving to inactivate motor 120 when the travel limits of control lever 24 in arcuate track 70 have been reached. The extend-retract operative mode of the landing member 26, as effected by actuator motor 86, is controlled by spring centered potentiometer 132 which serves as a motor control switch, with limit switches 134 and 136 serving to inactivate motor 86 at the outer limits of travel of the landing member. The outboard linear position sensor 138 is connected in series with the extend circuit of motor 86 such that the extend circuit of motor 86 is opened when the null position of sensor 138 is attained. The up and down movement of the ramp assembly, as effected by motor 112, is controlled by a spring centered potentiometer 140 which serves as a motor control switch, with limit switches 142 and 144 being suitably placed to limit the upward and downward movement of the ramp assembly. Once an object such as an aircraft is contacted by the outboard end of the landing assembly, upward movement of the ramp assembly could also cause compression of the snubber 106 against the aircraft and therefor a normally closed relay switch 146 is provided to open the circuit to motor 112 when the linear position sensor 138 reaches a null position, after which upward or downward positioning of the ramp assembly may not be continued until the landing member 26 is retracted by the operator. If airplane movement occurs, such as to compress sensor 138 past the null position, the retract circuit of motor 86 will be actuated to cause the landing member 26 to retract until the null position is reached again. Access ramp lights and floor heaters are controlled by switches 148 and 150, respectively. A power on light 152 is also provided.

Referring now to FIGS. 1, 2, and 3, left and right hand hinged guard rail assemblies 156 are mounted on the ramp assembly for upward and downward movement therewith, left and right hand guard rail assemblies 158 are mounted on the outboard landing assembly 12 for extending and retracting movement therewith, and left and right hand inverted channel shrouds 160 encase the arms 18 and tie rods and the pivot arm 54, all of which function to not only enhance the appearance of the structure but also to provide for its safe usage. The electrical control panel 154 may be conveniently located at the outboard end of one of the guard rail assemblies 158 as shown in FIG. 1. The outboard end section of the landing member 26 may be provided with an extended section as shown in FIG. 2 and separated by a gate portion 158a to permit an airplane passenger entry door to be opened from outside the airplane by an operator standing on the outboard end section of the landing member 26, the gate being closable before loading or unloading of passengers.

It is believed that the invention will have been clearly understood from the foregoing detailed description of my now-preferred illustrated embodiment. Changes in the details of construction may be resorted to without departing from the spirit of the invention and it is accordingly my intention that no limitations be implied and that the hereto annexed claims be given the broadest interpretation to which the employed language fairly admits. For example, the ramp assembly may provide a conveyor floor ramp leading to the outboard landing assembly which also provides a conveyor landing member for cargo loading and unloading. In such an embodiment, suitable means would be provided to drive the ramp assembly and outboard landing assembly conveyors.

The embodiments of an invention in which an exclusive property or privilege is claimed are defined as follows:

1. An access ramp which comprises a ramp assembly comprising a plurality of tread members, tread mounting means mounting said tread members and adapted to be hingeably connected to a supporting structure at an inboard end for upward and downward movement about the hinged connection, supporting means parallel to the tread mounting means and adapted to be hingedly connected to a supporting structure at an inboard end for upward and downward movements about the hinged connection, articulating means linking said tread members and said tread mounting means whereby said tread members may selectively be positioned irrespective of the ramp position in a first mode wherein the treads are in alignment forming a substantially planar surface parallel to said tread mounting means and a second mode wherein the treads are substantially horizontal forming a stairway; an outboard landing assembly comprising a landing member, and a landing mounting means mounting said landing member and connected to an outboard end of said tread mounting means and to an outboard end of said supporting means, said landing member being positioned by said landing mounting means to be operable in conjunction with said tread members in both their ramp and stair modes; and elevator means for supporting and raising and lowering the outboard end of said ramp as-' sembly.

2. The access ramp of claim 1 wherein said tread mounting means includes left and right hand mounting arms; wherein said tread members include left and right hand pivot arms journal mounted to the respective mounting arms; and wherein said articulated means is pivotally connected to said pivot arms and to said mounting arms.

3. The access ramp of claim 2 said articulated means includes left and right hand links joined together endwise and pivotally connected to the respective pivot arms, left and right lever arms pivotally connected to said links and to said mounting arms for positional control of said tread members, and means operably connected to said lever arms for controlling the position of said lever arms relative to said mounting arms when said mounting arms are raised or lowered.

4. The access ramp of claim 1 wherein said tread mounting means includes left and right hand mounting arms; and wherein said landing mounting means comprises left and right hand mounting brackets mounted to the outboard ends of the respective tread mounting arms and left and right hand guide means movably mounting said landing member to said mounting brackets such that said landing member can be extended from and retracted to a position underneath said tread members, and means operably connected to said landing member for extending and retracting said landing member.

5. The access ramp of claim 4 wherein said outboard landing assembly includes an outboard docking assembly mounted by the outboard end of said landing member and adapted to dock against an object aligned askew to said landing member.

6. An access ramp which comprises left and right hand tread member mounting arms adapted to be hingeably connected to a supporting structure only at their inboard ends for upward and downward movement about the hinged connection; a plurality of tread members pivotally journalled to said mounting arms; left and right hand articulating links connected endwise and pivotally connected to said tread members and to the respective left and right hand mounting arms at the inboard ends, said left and right hand mounting arms and articulating links being parallel with the respective points of pivotal connection to the tread members being aligned and equidistant from one another; left and right hand lever arms pivotally mounted to the respective mounting arms and articulating links for positional control of said tread members; means operably connected to said lever arms for controlling the position of said lever arms relative to said mounting arms to maintain said tread members in either a ramp mode or a stair mode when said mounting arms are either raised or lowered; left and right hand ramp support arms hingeably mounted to the outboard ends of the respective left and right hand mounting arms and adapted to be hingeably connected to a supporting structure; and elevator means mounted to said ramp support arms and adapted to be connected to a supporting structure for raising and lowering said ramp support arms and said mounting arms about the respective hinged connections.

7. The access ramp of claim 6 including an outboard landing assembly comprising left and right mounting brackets pivotally interconnecting the outboard ends of the respective left and right mounting arms and support arms; a landing member; left and right hand guide means movably mounting said landing member to said mounting brackets such that said landing member can be extended from and retracted to a position underneath said tread members; and means operably connected to said landing member for extending and retracting said landing memher.

8. An access ramp which comprises a ramp assembly comprising a ramp floor mounting means adapted to be hingeably connected to a supporting structure at an inboard end for upward and downward movement about the hinged connection, means providing a ramp floor mounted between said ramp floor mounting means, ramp support means hingeably mounted to the outboard end of the ramp floor mounting means and adapted to be hingeably connected to a supporting structure, elevator means mounted to said ramp support means and adapted to the connected two-way supporting structure for raising and lowering said ramp support means and said ramp for mounting means about the respective hinged connections; and an outboard landing assembly comprising landing member mounting means pivotally interconnected to the outboard end of the mounting means and support means, a landing member movably mounted by said landing member mounting means such that said landing member can be extended from and retracted to a position underneath said floor member, and means operably connected to said landing member for extending and retracting said landing member.

9. The access ramp of claim 8 wherein said rarnp floor mounting means comprises left and right hand ramp floor mounting arms positioned on opposite sides of said ramp floor; and wherein said ramp support means comprises left and right hand ramp support arms positioned adjacent to the respective left and right hand floor mounting arms so as to define with the ramp supporting structure, the landing member mounting means, and the ramp floor mounting arms a parallelogram configuration such that said ramp member will remain horizontal at all attitudes of said ramp assembly.

10. The access ramp of claim 9 wherein said landing member mounting means comprises left and right hand brackets pivotally interconnected to the outboard ends of the respective left and right hand mounting arms and support arms; and including left and right hand guide means movably mounting said landing member to said mounting brackets.

References Cited UNITED STATES PATENTS 479,436 7/1892 Lummus 182--86XR 655,923 8/1900 Dutton 182 86 X=R 1,166,141 12/1915 Merrettig 182-86 XR 1,343,094 6/1920 Sims 182 86 1,419,834 6/1922 Fellows 182-86X1R 1,590,317 6/1926 Richards 14 71 3,008,158 11/1961 Stinson 14-71 3,391,416 7/1968 Riggles 1471 JACOB L. NACKENOFF, Primary Examiner U.S. o1.X.R. 182-86 

